The South Cayuga Old Order Mennonite meetinghouse at Dunnville, Ontario was located on the north side of Rainham Road at the west end of South Cayuga. Minister John D. Shirk served as the last non-salaried Old Order leader. In 1925 there were 20 members; in 1950, 2. The congregation dissolved in 1941. It had been affiliated with the Old Order Mennonites from 1889-1930 and with the Markham-Waterloo Mennonite Conference from 1930-41. The first building was occupied in 1850.